Dr. Terrence Sejnowski

M.Sc. Orlando Trejo

Transcription

Welcome back to Learning How to Learn. Today we're going to talk about how to become a better learner. As we learn more about the brain we can become better learners, and here are two tips for how to learn better. Tip number one, the best gift that you can give your brain is Physical Exercise. We once thought that all of the neurons in your brain were already present at birth, but we now know that in a few places, new neurons are born every day. One of these places is in your Hippocampus, a brain area that is very important for learning new things that we already discussed earlier in the course. In this experiment, a rat is shown, learning how to distinguish a picture of a flower from a picture of an airplane. In the background is a photo of neurons in the hippocampus, with the old neurons shown in blue and newly generated neurons in red. As the rat learns the task, these new neurons are recruited to help perform better pattern separation between the two pictures. These new neurons help you learn new things but they will die if you don't use them. New experiences will rescue them. Exercise, interestingly, also helps new neurons survive. Exercise is by far, more effective than any drug on the market today to help you learn better. It benefits all of your vital organisms, not just your brain. It is unfortunate that schools are dropping gym and recess to make room for more instruction. Gym and recess are by far the most important parts of the curriculum. Here's another tip and this has to do with practice making perfect, but only when your brain is prepared. There are certain critical periods in the development of your brain. When sudden improvements occur in specific abilities, expect them to happen and prepare your brain for them. The critical period for first language acquisition extends up to puberty. One of the best studied critical periods in the brain is when binocular depth perception or stereopsis matures during the first two years of life. Stereopsis is the magic behind Magic Eye pictures like the one shown here. If you stare at this image and slightly cross your eyes, you will see staircases pop out of the page. There is a slight shift between the images in the two eyes and your brain interprets this slight shift as difference in depth. Not everyone, however, can see this. Over 5% of the population is stereo blind. If the two eyes are not properly aligned during the first two years of development, the neurons in your visual cortex will fail to properly strengthen the inputs from the two eyes and depth perception is permanently impaired. Well, that's the dogma. But Sue Barry, a friend of mine from graduate school at Princeton, was able to recover stereo vision through eye exercises. And wrote a book about it, entitled Fixing My Gaze, a scientist's journey into seeing in three dimensions. Practice can repair, as well as train the brain. But this takes much longer, past the critical period. This brings us to zombies. Zombies can't learn. It is also clear from their behavior that they have brain damage. Especially in the front of their cortex, which is the part that makes plans, as well as in their language areas. Learning, Planning, Language, these are the skills that make us human. The prefrontal cortex is also involved in complex analysis in social behaviors, as well as decision making and planning. It is the last part of the cortex to mature, so until this happens, there may be a little bit of zombie in you. Another patient, EVR, suffered a stroke in the social parts of his prefrontal cortex. EVR had a high IQ and seemed normal, but he was ruined by making bad financial decisions and bad social interactions. He lost both his home and his family. Good judgement takes a long time, and a lot of experience to acquire. Learning, is too important to be left behind in the classroom. Learning to learn is a skill you can master. And you can use it to improve every part of your life. You'll be learning even more learning tips this week, and can follow up on them at brainfacts.org. I'm Terry Sejnowski, happy learning to you until we meet again.